1. Field of Invention
The current invention relates to materials for electronic and/or electro-optic devices and devices using the materials, in particular to hybrid semiconducting-dielectric materials and devices using the hybrid semiconducting-dielectric materials.
2. Discussion of Related Art
Performance of organic field-effect transistors (OFET) at voltages <10 V is limited by the nature of the typical gate dielectrics. These dielectrics typically have capacitance in the range of 1-20 nF/cm2 because they are designed for minimum leakage current at absolute applied voltages of 100 V. The most commonly used dielectric materials are thermally grown silicon oxide and spincoated vinyl polymers. OFETs using these gate dielectrics require tens of volts on the gate to achieve on/off ratios >1000. In addition, the source-drain separation (device length L) must be at least one micron to avoid short channel effects that also reduce modulation. (J. N. Haddock, X. H. Zhang, S. J. Zheng, Q. Zhang, S. R. Marder, and B. Kippelen, “A comprehensive study of short channel effects in organic field-effect transistors,” Organic Electronics 7, 45 (2006); M. D. Austin and S. Y. Chou, “Fabrication of 70 nm channel length polymer organic thin-film transistors using nanoimprint lithography,” Applied Physics Letters 81, 4431 (2002); J. Collet, O. Tharaud, A. Chapoton, and D. Vuillaume, “Low-voltage, 30 nm channel length, organic transistors with a self-assembled monolayer as gate insulating films,” Applied Physics Letters 76, 1941 (2000); L. Torsi, A. Dodabalapur, and H. E. Katz, “An Analytical Model For Short-Channel Organic Thin-Film Transistors,” Journal Of Applied Physics 78, 1088 (1995); K. Tsukagoshi, F. Fujimori, T. Minari, T. Miyadera, T. Hamano, and Y. Aoyagi, “Suppression of short channel effect in organic thin film transistors,” Applied Physics Letters 91 (2007). Y. J. Zhang, J. R. Petta, S. Ambily, Y. L. Shen, D. C. Ralph, and G. G. Malliaras, “30 nm channel length pentacene transistors,” Advanced Materials 15, 1632 (2003).) Larger gate lengths severely limit accessible switching speed, which is inversely proportional to (L2).
Particular advances in circuit technology include greatly reduced power consumption through high-capacitance gates and greater complexity from advanced patterning methods. For example, the combination of alumina and an overlying phosphonic acid self-assembled monolayer as a gate dielectric led to 1-V transistors and inverters with gain of 100 and kHz speed. (H. Klauk, U. Zschieschang, J. Pflaum, and M. Halik, “Ultralow-power organic complementary circuits,” Nature 445, 745 (2007).) An even higher gain of 500 in a low-voltage inverter resulted from high-mobility (>0.5 cm2/Vs) organic films and high-C Ta2O5. (S. Tatemichi, M. Ichikawa, S. Kato, T. Koyama, and Y. Taniguchi, “Low-voltage, high-gain, and high-mobility organic complementary inverters based on N,N′-ditridecyl-3,4,9,10-perylenetetracarboxylic diimide and pentacene,” Physica Status Solidi-Rapid Research Letters 2, 47 (2008).) C60 was an alternative n-material for a gain-100 inverter. (M. Kitamura and Y. Arakawa, “Low-voltage-operating complementary inverters with C-60 and pentacene transistors on glass substrates,” Applied Physics Letters 91 (2007).) Variously substituted Perylene tetracarboxylic diimides (PTCDIs) were used with pentacene in inverters. (M. M. Ling, Z. N. Bao, P. Erk, M. Koenemann, and M. Gomez, “Complementary inverter using high mobility air-stable perylene di-imide derivatives,” Applied Physics Letters 90 (2007).) A new cyano PTCDI used with pentacene gave a flip-flop with 5 kHz clock speed and ca. 20 microsecond delay times. (B. Yoo, A. Madgavkar, B. A. Jones, S, Nadkarni, A. Facclietti, K. Dimmler, M. R. Wasielewski, T. J. Marks, and A. Dodabalapur, “Organic complementary D flip-flops enabled by perylene diimides and pentacene,” Ieee Electron Device Letters 27, 737 (2006).) Pentacene on poly(vinyl alcohol) was sufficient for a 1-kHz buffer. (D. W. Park, C. A. Lee, K. D. Jung, B. J. Kim, B. G. Park, H. Shin, and J. D. Lee, “Electrically stable organic thin-film transistors and circuits using organic/inorganic double-layer insulator,” Japanese Journal Of Applied Physics Part 1-Regular Papers Brief Communications & Review Papers 46, 2640 (2007).) Other examples of organic or polymer-based circuits include complete active matrix display backplanes, shift registers, sensor networks, and radio frequency transponders. (T. Someya, Y. Kato, T. Sekitani, S. Iba, Y. Noguchi, Y. Murase, H. Kawaguchi, and T. Sakurai, “Conformable, flexible, large-area networks of pressure and thermal sensors with organic transistor active matrixes,” Proceedings Of The National Academy Of Sciences Of The United States Of America 102, 12321 (2005); L. S. Zhou, A. Wanga, S. C. Wu, J. Sun, S. Park, and T. N. Jackson, “All-organic active matrix flexible display,” Applied Physics Letters 88 (2006); G. H. Gelinck, H. E. A. Huitema, E. Van Veenendaal, E. Cantatore, L. Schrijnemakers, J. Van der Putten, T. C. T. Geuns, M. Beenhakkers, J. B. Giesbers, B. H. Huisman, E. J. Meijer, E. M. Benito, F. J. Touwslager, A. W. Marsman, B. J. E. Van Rens, and D. M. De Leeuw, “Flexible active-matrix displays and shift registers based on solution-processed organic transistors,” Nature Materials 3, 106 (2004); P. F. Baude, D. A. Ender, M. A. Haase, T. W. Kelley, D. V. Muyres, and S. D. Theiss, “Pentacene-based radio-frequency identification circuitry,” Applied Physics Letters 82, 3964 (2003).)
The majority of organic semiconductors (OSCs) are hole-carrying materials; only a handful of high-quality air-stable n-channel materials have been discovered. Holes are generally more stable than electrons in conjugated organic systems when exposed to the ambient atmosphere. Air-stable n-channel OSCs should also be designed to be robust against environmental quenchers such as oxygen, synthetic residues, and water.
While hundreds of p-organic semiconductors with mobilities useful for plastic electronics have now been reported, there are still considerably fewer n-OSCs. While for some applications, p-OSCs alone would be sufficient, n-OSCs are needed for the more power-efficient complementary transistor circuits, as well as for devices that relay on p-n junctions, such as thermoelectric modules and solar cells. Limitations on possible pi-frameworks for n-OSCs arise because of the generally more limited stability of injected electrons relative to environmental quenchers such as oxygen and synthesis residues in and around organic semiconductors. For thermodynamic stability of the radical anion to oxygen and water, the reduction potential of an n-OSC would need to be more positive than the standard calomel electrode (SCE). (D. M. deLeeuw, M. M. J. Simenon, A. R. Brown, and R. E. F. Einerhand, “Stability of n-type doped conducting polymers and consequences for polymeric microelectronic devices,” Synthetic Metals 87, 53 (1997).) At such positive potentials, n-OSCs are of limited use for transistor applications because of the ease of environmental doping that causes high off currents.
Even with respect to water, the stability window of n-OSCs in n-channel organic field effect transistors (OFETs) is more limited than for p-OSCs. (deLeeuw, D. M.; Simenon, M. M. J.; Brown, A. R.; Einerhand, R. E. F. Synthetic Metals 1997, 87, 53-59.) Approaches to increasing stability originally involved fluorination of either the core conjugated groups or side chains. The specific molecule hexadecafluoro copper phthalocyanine (F16-CuPc) (Bao, Z. A.; Lovinger, A. J.; Brown, J. Journal Of The American Chemical Society 1998, 120, 207-208) was made stable to electron transport by the lowering of its lowest unoccupied molecular orbital (LUMO) energy by the fluoro groups on the conjugated system. (Ghosh, A.; Gassman, P. G.; Almlof, J. Journal Of The American Chemical Society 1994, 116, 1932-1940.; Schlettwein, D.; Hesse, K.; Gruhn, N. E.; Lee, P. A.; Nebesny, K. W.; Armstrong, N. R. Journal Of Physical Chemistry B 2001, 105, 4791-4800.) Another class of condensed ring compounds, naphthalenetetracarboxylic diimides (NTCDIs), especially the N,N′-bis(pentadecafluorooctyl) derivative, “F15”), are apparently stabilized to electron transport, with mobility up to 0.1 cm2/Vs, by fluoro substitution on side chains far enough from the conjugated system to have little effect on the orbital energy levels, but close enough to provide protection against chemical quenching. (Kao, C. C.; Lin, P.; Lee, C. C.; Wang, Y. K.; Ho, J. C.; Shen, Y. Y. Applied Physics Letters 2007, 90.; Katz, H. E.; Lovinger, A. J.; Johnson, J.; Kloc, C.; Siegrist, T.; Li, W.; Lin, Y. Y.; Dodabalapur, A. Nature 2000, 404, 478.; Katz, H. E.; Otsuki, J.; Yamazaki, K.; Suka, A.; Takido, T.; Lovinger, A. J.; Raghavachari, K. Chemistry Letters 2003, 32, 508-509.; Hosoi, Y.; Tsunami, D.; Hisao, I.; Furukawa, Y. Chemical Physics Letters 2007, 436, 139-143.; Katz, H. E.; Johnson, J.; Lovinger, A. J.; Li, W. J. J. Am. Chem. Soc. 2000, 122, 7787-7792.) Since then, the majority of high quality n-channel materials have been based on either naphthalene or perylene tetracarboxylic diimides. (Katz, H. E.; Lovinger, A. J.; Johnson, J.; Kloc, C.; Siegrist, T.; Li, W.; Lin, Y. Y.; Dodabalapur, A. Nature 2000, 404, 478.; Chen, H. Z.; Ling, M. M.; Mo, X.; Shi, M. M.; Wang, M.; Bao, Z. Chem. Mater. 2007, 19, 816-824.; Jones, B. A.; Ahrens, M. J.; Yoon, M. H.; Facchetti, A.; Marks, T. J.; Wasielewski, M. R. Angewandte Chemie-International Edition 2004, 43, 6363-6366.; Schmidt, R.; Ling, M. M.; Oh, J. H.; Winkler, M.; Könemann, M.; Bao, Z.; Wiirthner, F. Adv. Mater. 2007, 19, 3692-3695.; Shukla, D.; Nelson, S. F.; Freeman, D. C., US Patent Application US20060237712A1; Shukla, D.; Freeman, D. C.; Nelson, S. F., US Patent Application US20060134823A1; Shukla, D.; Freeman, D. C.; Nelson, S. F.; Carey, J. T.; Ahearn, W. G., US Patent Application US20070116895A1; Shukla, D.; Freeman, D. C.; Nelson, S. F.; Carey, J. T.; Ahearn, W. G., US Patent Application US20070096084A1.) Vacuum sublimation of these materials, usually at elevated substrate temperatures, results in highly crystalline films. Perylene tetracarboxylic diimides (PTCDIs) (Jones, B. A.; Ahrens, M. J.; Yoon, M. H.; Facchetti, A.; Marks, T. J.; Wasielewski, M. R. Angewandte Chemie-International Edition 2004, 43, 6363-6366.; Chen, H. Z.; Shi, M. M.; Aernouts, T.; Wang, M.; Borghs, G.; Heremans, P. Solar Energy Materials And Solar Cells 2005, 87, 521-527.; Tatemichi, S.; Ichikawa, M.; Koyama, T.; Taniguchi, Y. Applied Physics Letters 2006, 89.; Jones, B. A.; Facchetti, A.; Marks, T. J.; Wasielewski, M. R. Chemistry Of Materials 2007, 19, 2703-2705.; Wurthner, F.; Osswald, P.; Schmidt, R.; Kaiser, T. E.; Mansikkamaki, H.; Konemann, M. Organic Letters 2006, 8, 3765-3768.; Ling, M. M.; Eric, P.; Gomez, M.; Koenemann, M.; Locklin, J.; Bao, Z. N. Advanced Materials 2007, 19, 1123-1127) have been stabilized by substitution with cyanos, chloros, fluoros, and pentadecafluoroalkyls. Jones et al. showed that cyanated PTCDI cores with perfluoroalkyl chains gave a maximum mobility of 0.64 cm2/Vs while Chen et al. achieved air stable mobilities of 0.068 cm2/Vs for a bis(perfluorophenyl) PTCDI compound. (Chen, H. Z.; Ling, M. M.; Mo, X.; Shi, M. M.; Wang, M.; Bao, Z. Chem. Mater. 2007, 19, 816-824.; Jones, B. A.; Ahrens, M. J.; Yoon, M. H.; Facchetti, A.; Marks, T. J.; Wasielewski, M. R. Angewandte Chemie-International Edition 2004, 43, 6363-6366.) Recently, air stable core-fluorinated PTCDI compounds were reported with a maximum mobility in air of 0.338 cm2/Vs. (Schmidt, R.; Ling, M. M.; Oh, J. H.; Winkler, M.; Könemann, M.; Bao, Z.; Wiirthner, F. Adv. Mater. 2007, 19, 3692-3695.)
Recently, sufficient electron-withdrawing groups and annealing processes have been used with oligothiophenes (Yoon, M. H.; DiBenedetto, S. A.; Facchetti, A.; Marks, T. J. Journal Of The American Chemical Society 2005, 127, 1348-1349.; Letizia, J. A.; Facchetti, A.; Stern, C. L.; Ratner, M. A.; Marks, T. J. Journal Of The American Chemical Society 2005, 127, 13476-13477.; Ie, Y.; Nitani, M.; Ishikawa, M.; Nakayama, K.; Tada, H.; Kaneda, T.; Aso, Y. Organic Letters 2007, 9, 2115-2118.; Yoon, M. H.; Facchetti, A.; Stern, C. E.; Marks, T. J. Journal Of The American Chemical Society 2006, 128, 5792-5801.; Cai, X. Y.; Burand, M. W.; Newman, C. R.; da Silva, D. A.; Pappenfus, T. M.; Bader, M. M.; Bredas, J. L.; Maim, K. R.; Frisbie, C. D. Journal Of Physical Chemistry B 2006, 110, 14590-14597) (perfluoroacyls, perfluorophenyls, polycyanovinyls, difluoromethylenes), aza heterocycles (Mamada, M.; Nishida, J.; Kumaki, D.; Tokito, S.; Yamashita, Y. Chemistry of Materials 2007, 19, 5404-5409.; Ando, S.; Murakami, R.; Nishida, J.; Tada, H.; Inoue, Y.; Tokito, S.; Yamashita, Y. Journal Of The American Chemical Society 2005, 127, 14996-14997.; Kojima, T.; Nishida, J.; Tokito, S.; Yamashita, Y. Chemistry Letters 2007, 36, 1198-1199.; Naraso; Nishida, J.; Kumaki, D.; Tokitp, S.; Yamashita, Y. Journal Of The American Chemical Society 2006, 128, 9598-9599) and a terthienoquinoid (Handa, S.; Miyazaki, E.; Takimiya, K.; Kunugi, Y. J. Am. Chem. Soc. 2007, 129, 11684-11685) to allow high-mobility, low-threshold voltage (Vt) performance in vacuum and in some cases in air (Jones, B. A.; Ahrens, M. J.; Yoon, M. H.; Facchetti, A.; Marks, T. J.; Wasielewski, M. R. Angewandte Chemie-International Edition 2004, 43, 6363-6366).
Approaches utilizing carbonyl functionalized quaterthiophenes and anthracenedicarboximides have yielded maximum mobilities of 0.34 cm2/Vs in vacuum for the former and 0.02 cm2/Vs in air for the latter. (Yoon, M. H.; DiBenedetto, S. A.; Russell, M. T.; Facchetti, A.; Marks, T. J. Chem. Mater. 2007, 19, 4864-4881.; Wang, Z.; Kim, C.; Facchetti, A.; Marks, T. J. J. Am. Chem. Soc. 2007, 129, 13362-13363.) Promising results have also been obtained with the impressively synthesized perfluoropentacene (Inoue, Y.; Sakamoto, Y.; Suzuki, T.; Kobayashi, M.; Gao, Y.; Tokito, S. Japanese Journal Of Applied Physics Part 1-Regular Papers Short Notes & Review Papers 2005, 44, 3663-3668), aza-acenes (Nishida, J.; Naraso; Murai, S.; Fujiwara, E.; Tada, H.; Tomura, M.; Yamashita, Y. Organic Letters 2004, 6, 2007-2010), and a ladder polymer (Babel, A.; Jenekhe, S. A. Journal of the American Chemical Society 2003, 125, 13656-13657). Nanowire, co-oligomer, and liquid crystal assembly of perylenediimides have also been useful. (Briseno, A. L.; Mannsfeld, S. C. B.; Reese, C.; Hancock, J. M.; Xiong, Y.; Jenekhe, S. A.; Bao, Z.; Xia, Y. Nano Letters 2007, 7, 2847-2853.; Zhan, X. W.; Tan, Z. A.; Domercq, B.; An, Z. S.; Zhang, X.; Barlow, S.; Li, Y. F.; Zhu, D. B.; Kippelen, B.; Marder, S. R. Journal Of The American Chemical Society 2007, 129, 7246-+.; Singh, T. B.; Erten, S.; Gunes, S.; Zafer, C.; Turkmen, G.; Kuban, B.; Teoman, Y.; Sariciftci, N. S.; Icli, S. Organic Electronics 2006, 7, 480-489.) C60 also continues to be of interest. (Zhang, X. H.; Domercq, B.; Kippelen, B. Applied Physics Letters 2007, 91.; Na, J. H.; Kitamura, M.; Arakawa, Y. Appl. Phys. Lett. 2007, 91, 193501.)
Thermally evaporated thin films of various N,N′-disubstituted NTCDIs demonstrated high field effect electron mobilities both in vacuum and in air. (H. E. Katz, J. Johnson, A. J. Lovinger, and W. J. Li, “Naphthalenetetracarboxylic diimide-based n-channel transistor semiconductors: Structural variation and thiol-enhanced gold contacts,” Journal Of The American Chemical Society 122, 7787 (2000); H. E. Katz, A. J. Lovinger, J. Johnson, C. Kloc, T. Siegrist, W. Li, Y. Y. Lin, and A. Dodabalapur, “A soluble and air-stable organic semiconductor with high electron mobility,” Nature 404, 478 (2000).) These materials exhibited mobilities on the order of 10−1 cm2/Vs, an orders-of-magnitude improvement over most previous n-channel materials. (J. G. Laquindanum, H. E. Katz, A. Dodabalapur, and A. J. Lovinger, “n-channel organic transistor materials based on naphthalene frameworks,” Journal Of The American Chemical Society 118, 11331 (1996).) This is consistent with a favorable two-dimensional crystalline film morphology. More importantly, by incorporating perfluoroalkyl chains at the N,N′ positions these high mobilities may be achieved in air. These side chains were far enough from the conjugated core to have little effect on the reduction potentials, which were >0.5 V more negative than SCE. Thus, side chains with cross-sections comparable to those of the NTCDI cores add special kinetic stability to transported electrons. (R. T. Weitz, K. Amsharov, U. Zschieschang, E. B. Villas, D. K. Goswami, M. Burghard, H. Dosch, M. Jansen, K. Kern, and H. Klauk, “Organic n-channel transistors based on core-cyanated perylene carboxylic diimide derivatives,” Journal Of The American Chemical Society 130, 4637 (2008).) Even a single CF3 group on a small side chain such as benzyl greatly increased air stability (H. E. Katz, J. Johnson, A. J. Lovinger, and W. J. Li, “Naphthalenetetracarboxylic diimide-based n-channel transistor semiconductors: Structural variation and thiol-enhanced gold contacts,” Journal Of The American Chemical Society 122, 7787 (2000); H. E. Katz, A. J. Lovinger, J. Johnson, C. Kloc, T. Siegrist, W. Li, Y. Y. Lin, and A. Dodabalapur, “A soluble and air-stable organic semiconductor with high electron mobility,” Nature 404, 478 (2000)); C. C. Kao, P. Lin, C. C. Lee, Y. K. Wang, J. C. Ho, and Y. Y. Shen, “High-performance bottom-contact devices based on an air-stable n-type organic semiconductor N,N-bis (4-trifluoromethoxybenzyl)-1,4,5,8-naphthalene-tetracarboxylic di-imide,” Applied Physics Letters 90 (2007); Y. L. Lee, H. L. Hsu, S. Y. Chen, and T. R. Yew, “Solution-processed naphthalene diimide derivatives as n-type semiconductor materials,” Journal Of Physical Chemistry C 112, 1694 (2008); Y. Hosoi, D. Tsunami, I. Hisao, and Y. Furukawa, “Air-stable n-channel organic field-effect transistors based on N,N′-bis(4-trifluoromethylbenzyl)perylene-3,4,9,10-tetracarboxylic diimide,” Chemical Physics Letters 436, 139 (2007).) More recently, other researchers have demonstrated high mobilities from other large-cross-section side chains, such as cyclohexyl (D. Shukla, D. C. Freeman, S. F. Nelson, J. T. Carey, and W. G. Aheam, in United States Patent and Trademark Office, United States, (2007)), substitution of the NTCDI core with electron-withdrawing groups to increase thermodynamic stability of radical anions (B. A. Jones, A. Facchetti, T. J. Marks, and M. R. Wasielewski, “Cyanonaphthalene diimide semiconductors for air-stable, flexible, and optically transparent n-channel field-effect transistors,” Chemistry Of Materials 19, 2703 (2007); C. Thalacker, C. Roger, and F. Wurthner, “Synthesis and optical and redox properties of core-substituted naphthalene diimide dyes,” Journal Of Organic Chemistry 71, 8098 (2006); C. Roger and F. Wurthner, “Core-tetrasubstituted naphthalene diimides: Synthesis, optical properties, and redox characteristics,” Journal Of Organic Chemistry 72, 8070 (2007)), and use of extended diimides such as PTCDIs. (C. Thalacker, C. Roger, and F. Wurthner, “Synthesis and optical and redox properties of core-substituted naphthalene diimide dyes,” Journal Of Organic Chemistry 71, 8098 (2006); H. Z. Chen, M. M. Ling, X. Mo, M. M. Shi, M. Wang, and Z. Bao, “Air stable n-channel organic semiconductors for thin film transistors based on fluorinated derivatives of perylene diimides,” Chemistry Of Materials 19, 816 (2007); R. Schmidt, M. M. Ling, J. H. Oh, M. Winkler, M. Konemann, Z. N. Bao, and F. Wurthner, “Core-fluorinated perylene bisimide dyes: Air stable n-channel organic semiconductors for thin film transistors with exceptionally high on-to-off current ratios,” Advanced Materials 19, 3692 (2007); T. B. Singh, S. Erten, S. Gunes, C. Zafer, G. Turkmen, B. Kuban, Y. Teoman, N. S. Sariciftci, and S. Icli, “Soluble derivatives of perylene and naphthalene diimide for n-channel organic field-effect transistors,” Organic Electronics 7, 480 (2006); M. M. Ling, P. Erk, M. Gomez, M. Koenemann, J. Locklin, and Z. N. Bao, “Air-stable n-channel organic semiconductors based on perylene diimide derivatives without strong electron withdrawing groups,” Advanced Materials 19, 1123 (2007); J. H. Oh, S. Liu, Z. Bao, R. Schmidt, and F. Wurthner, “Air-stable n-channel organic thin-film transistors with high field-effect mobility based on N,N′-bis(heptafluorobutyl)3,4: 9,10-perylene diimide,” Applied Physics Letters 91 (2007); P. R. L. Malenfant, C. D. Dimitrakopoulos, J. D. Gelatine, L. L. Kosbar, T. O. Graham, A. Curioni, and W. Andreoni, “N-type organic thin-film transistor with high field-effect mobility based on a N,N-′-dialkyl-3,4,9,10-perylene tetracarboxylic diimide derivative,” Applied Physics Letters 80, 2517 (2002); S. Tatemichi, M. Ichikawa, T. Koyama, and Y. Taniguchi, “High mobility n-type thin-film transistors based on N,N′-ditridecyl perylene diimide with thermal treatments,” Applied Physics Letters 89 (2006); R. J. Chesterfield, J. C. McKeen, C. R. Newman, P. C. Ewbank, D. A. da Silva, J. L. Bredas, L. L. Miller, K. R. Mann, and C. D. Frisbie, “Organic thin film transistors based on N-alkyl perylene diimides: Charge transport kinetics as a function of gate voltage and temperature,” Journal Of Physical Chemistry B 108, 19281 (2004)), anthracenedicarboximides (Z. Wang, C Kim, A. Facchetti, and T. J. Marks, “Anthracenedicarboximides as air-stable n-channel semiconductors for thin-film transistors with remarkable current on-off ratios,” Journal Of The American Chemical Society 129, 13362 (2007); H. E. Katz, W. Li, and A. J. Lovinger, edited by U.S. P. a. T. Office, United States, 2001)) and higher rylenes (F. Nolde, W. Pisula, S. Muller, C. Kohl, and K. Mullen, “Synthesis and self-organization of core-extended perylene tetracarboxdiimides with branched alkyl substituents,” Chemistry Of Materials 18, 3715 (2006)).
A series of PTCDIs with small substituents such as core-chloro and -fluoro, and N-heptafluorobutyl and -phenethyl, showed mobilities of 0.1-0.7 cm2/Vs, with some retaining most of the mobility in air. (R. Schmidt, M. M. Ling, J. H. Oh, M. Winkler, M. Konemann, Z. N. Bao, and F. Wurthner, “Core-fluorinated rerylene bisimide dyes: Air stable n-channel organic semiconductors for thin film transistors with exceptionally high on-to-off current ratios,” Advanced Materials 19, 3692 (2007); M. M. Ling, P. Erk, M. Gomez, M. Koenemann, J. Locklin, and Z. N. Bao, “Air-stable n-channel organic semiconductors based on perylene diimide derivatives without strong electron withdrawing groups,” Advanced Materials 19, 1123 (2007); J. H. Oh, S. Liu, Z. Bao, R. Schmidt, and F. Wurthner, “Air-stable n-channel organic thin-film transistors with high field-effect mobility based on N,N′-bis(heptafluorobutyl)3,4: 9,10-perylene diimide,” Applied Physics Letters 91 (2007).) PTCDIs may be attached to polystyrene-acrylate diblocks, with mobility around 0.001 cm2/Vs. (S. Huttner, M. Sommer, and M. Thelakkat, “n-type organic field effect transistors from perylene bisimide block copolymers and homopolymers,” Applied Physics Letters 92 (2008).) In an embodiment, an electron-transporting polymer with mobility ca. 0.01 cm2/Vs was made by copolymerizing a PTCDI with dithienothiophene (X. W. Zhan, Z. A. Tan, B. Domercq, Z. S. An, X. Zhang, S. Barlow, Y. F. Li, D. B. Zhu, B. Kippelen, and S. R. Marder, “A high-mobility electron-transport polymer with broad absorption and its use in field-effect transistors and all-polymer solar cells,” Journal Of The American Chemical Society 129, 7246 (2007)). While some in-vacuum mobilities exceed 1 cm2/Vs, published mobilities in air are limited to about 0.6 cm2/Vs, and require multistep syntheses, awkward purification, and/or high temperature deposition. The most electron-demanding of these diimides are difficult to drive to fully insulating states.
In addition, solution-processed field effect transistor (FET) semiconductors are now of interest because of their potential contribution to low-cost fabrication of device arrays and circuits via mass manufacturing roll-to-roll processes using a combination of conventional coating and printing techniques. (H. Sirringhaus, Adv. Mater. 2005, 17, 2411-2425.; C. D. Dimitrakopoulos, P. R. L Malenfant, Adv. Mater. 2002, 14, 99-117.; T. Shimoda, Y. Matsuki, M. Furusawa, T. Aoki, I. Yudasaka, H. Tanaka, H. Iwasawa, D. Wang, M. Miyasaka, Y. Takeuchi, Nature 2006, 440, 784-786.; D. B. Mitzi, L. L. Kosbar, C. E. Murray, M. Copel, A. Afzali, Nature 2004, 428, 299-303.; H. E. Katz, A. J. Lovinger, J. Johnson, C. Kloc, T. Siegrist, W. Li, Y. Y. Lin and A. Dodabalapur, Nature 2000, 404, 478-481.). However, existing solution-processed FETs lack sufficiently high electron mobility.